Stepped Edge Ring Geometry for Wafer Bevel and Edge Deposition

Solution Overview

Problem

Conventional edge rings either fail to adequately suppress deposition at the bevel site of a wafer while maintaining deposition uniformity in the edge region, or they achieve good edge region uniformity at the cost of insufficient bevel site suppression.

Innovation Solution

An edge ring design featuring an annular body with a first step portion, an inclined portion, and a second step portion, along with passages that adjust the flow of backside gas to improve deposition characteristics at both the bevel and edge regions of a wafer.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-affected harmful factors

If conventional edge ring designs are used to suppress deposition at the bevel site, then deposition suppression at the bevel site is improved, but deposition distribution/uniformity in the edge region deteriorates

Engineering Contradiction:

Improvedeposition at bevel siteVSAvoiddeposition distribution in edge region

Core Design Contradiction:

Object-affected harmful factorsVSManufacturing precision

Solution Approach 1:

The edge ring is divided into multiple functional segments: a first step portion for suppressing bevel site deposition, an inclined portion for controlling gas flow, and a second step portion for maintaining edge region uniformity. Each segment performs a specific function to resolve the contradiction between bevel suppression and edge uniformity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different portions of the edge ring are designed with different geometries and functions: the first step portion (higher elevation) targets the bevel site for suppression, while the second step portion (lower elevation) targets the edge region for uniform deposition control. This local differentiation allows simultaneous optimization of both regions.

Inventive Principle:

Principle #3Local quality

2Manufacturing precision

If conventional edge ring designs are used to improve deposition distribution in the edge region, then deposition uniformity in the edge region is improved, but deposition suppression at the bevel site deteriorates

Engineering Contradiction:

Improvedeposition distribution in edge regionVSAvoiddeposition at bevel site

Core Design Contradiction:

Manufacturing precisionVSObject-affected harmful factors

Solution Approach 1:

The edge ring is divided into multiple functional segments: a first step portion for suppressing bevel site deposition, an inclined portion for controlling gas flow, and a second step portion for maintaining edge region uniformity. Each segment performs a specific function to resolve the contradiction between bevel suppression and edge uniformity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

Different portions of the edge ring are designed with different geometries and functions: the first step portion (higher elevation) targets the bevel site for suppression, while the second step portion (lower elevation) targets the edge region for uniform deposition control. This local differentiation allows simultaneous optimization of both regions.

Inventive Principle:

Principle #3Local quality

3Device complexity

If a simple annular edge ring is used, then device complexity is low, but deposition characteristics at both bevel and edge regions cannot be simultaneously optimized

Engineering Contradiction:

Improveedge ring structureVSAvoiddeposition characteristics

Core Design Contradiction:

Device complexityVSManufacturing precision

Solution Approach 1:

The edge ring is divided into multiple functional segments: a first step portion for suppressing bevel site deposition, an inclined portion for controlling gas flow, and a second step portion for maintaining edge region uniformity. Each segment performs a specific function to resolve the contradiction between bevel suppression and edge uniformity.

Inventive Principle:

Principle #1Segmentation

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The edge ring effectively suppresses deposition at the bevel site while maintaining uniform deposition in the edge region, enhancing overall deposition characteristics.

Implementation Method 1

A backside gas supplied between an end portion of a wafer and an edge ring through a backside gas channel may proceed toward the inclined bottom surface of the inclined portion

Methodology Applied

Scientific EffectGas flow redirection:

Data Source

PatentUS20260024732A1Edge ring, substrate processing apparatus having the same and method of manufacturing semiconductor device using the apparatus

Publication Date: 2026.01.22 SAMSUNG ELECTRONICS CO LTD

AI summary

A substrate processing system includes a substrate stage, a wafer, and an edge ring. The edge ring includes an annular shaped body portion, a first step portion having a first annular bottom surface positioned higher than an annular bottom surface of the annular shaped body portion by a first height, an inclined portion extending along an inner periphery of the first step portion, a second step portion extending along an inner periphery of the inclined portion, the second step portion vertically overlapping the wafer seated on the wafer seating surface, and a plurality of passages extending outwardly from the first annular bottom surface of the first step portion. A relationship between the first height and the distance between the second annular bottom surface and a top surface of the wafer third height controls a proportion of a backside gas that flows through the plurality of passages.